Electric-cable-coupling connecter



J. HIGHAM ELECTRIC CABLE CCUPLINC CONNECTER Sept. 25, 1928.

Filed Feb. 28, 1928 INVENTOR Patented Sept. 25, 1928.

kUNITED STATES 1,685,420 PATENT OFFICE.

JOHN HIGHAM, OF PORT RICHMOND, NEW YORK, ASSIGNOR TO DISPLAY STAGELIGHTING CO. INC., A CORPORATION OF NEW YORK..`

lELE CTRIC-CABLE-COUPLING CONNECTER.

Application filed February 28, 1928. Serial No. 257,564.

This invention relates to electrical fittings and more particularly isdirected to quick detachable electrical coupling connecters of improvedconstruction for joining portable circuit conductors to stage lightingunits, indus trial electric appliances and like apparatus.

-Among the objects of the invention is to generally improve portablecircuit electric connecters of the character described to provideseparable coupling structures comprising few and simple parts that arerugged, durable and being capable of withstanding the .hardest usage andwear, which shall be readily incorporated in circuit, easy and handy toseparate and connect, cheap to manufacture` and practical and efficientto a high degree in use.

Other objects of this invention will in part be obvious and in parthereinafter pointed out. Y

The invention accordingly consists in the features of construction,combinations of ele'- ments and arangement ofparts which will beexemplified in the construction hereinafter described and of which thescope of application will be indicated in the following claims.

In the accompanying drawing, in which is shown various possibleillustrative embodiments of this invention Fig. 1 is a top plan view ofan electric connecter embodying the invention incorporated in a portablecircuit, only a fragmentary portion of the circuit cables being shown.

Figs. 2, 3, 4, 5 and 6 are cross-sectional views taken on lines 2 2. 33, 4 4, 5 5

and 6 6, respectively in Fig. 1.

Fig. 7 is a top plan view of the female coupling block of the improvedconnecter with the cover piece removed.

Fig. 8 is a view of the inner side of the cover piece of the femalecoupling block.

Fig. 9 is a top` plan view of the male coupling block of the improvedconnecter with the cover piece removed, and

Fig. 10 is a view of the inner side of the cover piece of the malecoupling block.

Referring in detail to the drawing, 10 denotes a quick detachableelectric coupling connecter adapted to be incorporated in a 50 portablecircuit'for joining stage lighting units, industrial electric appliancesand the like apparatus to a suitable power-source (not shown). Onlyfragmentary portions of the power feed cable 11, and the appliancecable56 12 are .here shown. Preferably the power feed cable `11 joins thefemale block 13 of the connecter 10 to the power source and the cable 12joins the connecter male block 14 to the appliance (not shown) in thewell understood manner.

The female block 13 comprises a body piece 15, a cover piece 16demountab-ly attached to the body piece 15 by screws 20, and currentcarrying parts 17 permanently carried by the body piece 15l The pieces15 and 16 are machined structures made of insulating material cut fromcompressed block or sheetlibre in preference to being individuallymolded. Compressed bre for this purpose is commercially available at a.relatively 'cheap price and can be readily cut, drilled, threaded andmachined to form said pieces 15 and 16. Since the connecter 10 inservice is subjected to unusual hard and rough wear and abuse,

it has been found that insulating fibre stands up better under thesevere service to which it is subjected than individually molded ieces.Fibre is not only tough and resilient ut is practically immuned fromchipping, fracturing, crumbling or breaking. The ma- 8U chining requiredto form the improved device 10 as will hereinafter be described, are fewand simple so that a prac-tical and efiicient device can be produced atless cost than is possible to commercially produce the device 0f moldedpieces capable of 'withstanding to some fair degree the hard usage towhich the device is usually subjected. The body piece 15 may be of-rectan lar cross-section and has a part thereof cut away, said partbeing equivalentV in size and shape `to the cover piece 1G. The latteris made to just lill said cut away part and is substantially half thethickness of the body piece, over half the length thereof and equalthereto 1n width as is clearly shown in Figs. 1, 2, 7, 8, 9 and 10. j.

Spaced metallic contact receptacle members 18 of the current carryingparts17 are positioned to extend lengthwise through unout portion- 15nof the body plece 15. Said members 18 are snugly fitted into bored holes15b which extend in from an end surface 15c of said piece 15, the sleeveends 18b of the members 18 being set into said portion 15 below thelevel of the end surface 15c as at 15d. The lug or terminal ends 18a ofsaid members 18 extend into spaced recessle cut below the level of thesurface 15t of the piece 15. Sald recesses 15d communicate with the endsur- 110 i Threaded holes 19 are provided on opposite sides of thepassage 15" between the recesses 15 and the end surface 15g for engagingwith `the threaded end of screws 20.

The cover piece 16 has spaced recesses 16a cut below the level ofthesurface 16" thereof, said recesses 161 being positioned to mate .withthe recesses 15e of the piece 15 to form a housing about the terminalend 18". A single channel 16" is cut to extend below the level of thesurface 16" communicating the recesses 16n with the end surface of thepiece 16 corresponding to surface 15f ofthe piece 15. Said channel 16Cis formed with a smoothly ridged wall 16d and mates with the channel 15hto form a passage for the cable 11. Holes 21 are drilled through thepiece 16 in register with said threaded holes 19 wherethrough the screws20 extend for clamping thepiece 15 to 16 together.

The receptacle contact members 18l are preferably driven into positionand may be suitably' shaped to eliminate possible rotation in the boredholes 15". As here shown, said members 18 are of circular cross sectionand have their outer surface flute-d as at 18". The terminal lug end 18amay each carry a suitable binding post, such as the screw 22, forsecuring a bare end 11 of the conductor wire 11" of the feed cable 11.The recesses 15e may be spotted as at 15i to'provide clearance for theendsof the screw 21 as is shown in Fig. 2.

The female block 13 is fittedto terminate the end of the cable 11 bydismounting the cover piece 16 from the body piece 15 and attaching theconductor wire bared ends 11 to the terminal lugs 18 under the head ofthe screws 22. The cover piece 16 is then replaced with the end of thecable 11 extending lthrough the passage formed by channels 15 and 16".On tightening the clamping screws 20, portions of the insulating casing11c of the cable 11 are forced against the ridged walls 15i and 16'l ofsaid passage and are conformed to its contour thus forming an etlicientstra-in relief for the connection of the cable wires 11" with thecurrent carrying receptacle member 18. Said passage is proportioned incross section to securely clamp the cable 11 between the body and coverpieces yet permitsthe surfaces 15t and 16" to come into abutment so asto effect a complete closure about the live current carrying parts ofthe circuit therebetween.

The setting back of the sleeve ends 18" of the' contact receptaclemembers 18 from the end surface 15'c at 15d' aids in shielding the llvecurrent carrying members of the circuit which connect the mains or otherelectric power supply source from being short cire cuited or beingaccidentally con` acted with.

The male block 12 like the female portion 13 is also seen to comprise abody piece 25, a cover piece 26 demountably attached to the body piece,and current carrying part 27 permanently carried by the body piece 25.Said pieces 25 and 26 are made of the same material and may if desiredbe identical in construction with the pieces 15 and 16 of the femaleblock 13 described above. v A

As seen from the drawing, the piece 25 is of rectangular cross sectionof substantially the same construction, shape. length, width andthickness as piece 15. Spaced metallic contact prong members 28 of lthecurrent carrying parts 27 are snugly fitted to extend lengthwise throughbored holes 25'" in the uncut portion 25a of the body piece 25. Pinterminals 281 adapted to be inserted in sockets 18d of the sleeve ends18" of the female block 13 extend from said members 28 outwardly from anend surface 25". The lug or terminal ends 28" of said members 28 extendintol end surface 25g for engaging with the threaded ends of the screws30.

The cover "piece 26 which is made to fit the piece 25 like the coverpiece 16 fits the piece 15, described above, is provided with recesses26aL cut below the level of the surface 26" thereof. Said recesses 26mate with the recesses 25e of the piece 25 to house said terminal ends28". Hole 31 registerino with the threaded holes 29 for receivingtherein the clamping screws 30 which secure the pieces 25 and 26together. Each recess 263L communicates with the end surface 26g whichaligns with the end surface 25g through a ridged wall 26i of groove 26".The latter mating withlgrooves 25h to provide separate passages for eachcon- `ductor wire 12" ofthe cable 12.

The contact prong members 28 extend through bored holes 25" and havetheir outer surface fluted as at 28" to prevent rotatory movement ofsaid members in the holes. The terminal lug ends 28a of said memberseach carry a binding screw 32 for securing a bareend 12a of theconductor wire 12" of the cable 12. The recesses 25 may be spotted as at25i to provide clearance for the ends of the screw 31, as is shown inFig. 2.

The male portion 12 is fitted to terminate the end of the cable 11 byremoving the cover piece 26 from the body piece 25 and attaching aconductor wire bare ends 11 to each of the terminal lugs 28a under thehead of the .wires 12b are ing the clamping screws with the cableconductor wiresv 12b extending through the passages formed by thegrooves 25h and 26h, portions 12 ,of the insulation of t-he conductorressed int-o the ridged Wall passage 26l of t e cover piece 26 and areconformed to its contour, thus forming an efiicient strain relief forthe connection of the cable wire ends 12a with the binding screws 32.The grooves 25h and 2611 are proportioned to form the cross sections ofsaid passages to securely clamp the cable 12 between the body and coverpieces 25 and 26, respectively yet permits the surfaces 25t and 26b tocome into abutment so as to effect a complete closure about the currentcarrying parts of the connection of the cable 12 and members 28.

To provide a resilient contacting engagement of the pins 28a within thesockets 18d, said pins may be slitted lengthwise as at 28d to formspringy structures -as is shown in Figs. 3 ands9.

. The form of strain relief means incorporati ed in the femalev bloei.13 is best'suid for stalled in circuits can feedcables having arelatively thick insulating wall 11 over the conductor wires 11b, Whilethe strain relief means incorporated in the male portion 14 is desirablewhere the insulation Wall11 over the individual conductor wires 11b isrelatively thick. It is to be understood that either of the` connecterblocks may be made with either form of strain relief means., In bothforms of said means the cable or conductor wires are clamped betgeepinsulating pieces having at least half o t smooth-ridged surface whichserves to nonabrasively anchor the cables to the blocks WithoutinJuringf the insulation on the cable or conductor wire. Y, I Y

' The connecters 10 when assembled and inby merely uncoupling andcoupling the blocks 13 and 14 easily and quickly interchange lightingunits appliances or apparatus or disconnect them from the circuits withsafety.

It will thus be seen that there is provided a device in which theseveral objects of this invention are achieved and which is well adapted,to meet the conditions of practical use.

As various possible embodiments might be made of the above invention,and as various changes might be madein the embodiment above set forth,it is to be understood that all matter herein set forth or shown in theaccompanying drawing is to be interpreted as illustrative and not in a.limiting sense.

Having thus described my invent-ion, I claim-as-new and desire to secureby Letters Patent: f

il. In connecters for coupling electric insulated wire cableslof thecharacter described', a block formed of machined fibrous sheet materialcomprising a. body piece having a cut Vthe cable end being pressed epassage wall thereof formed with a away portion and a` cover piece, saidcover piece being substantially equivalentin shape and dimensions tosaid cut awayy portion, spaced metallic contact members driven throughan uncut portion of the body piece, said pieces having mating recessesbored in surfaces thereof toform avhousing about an inner end 0f each ofsaid members when the cover piece is applied to replace said cut awayportion, a binding post carried by each of said inner ends within saidhousing, screw fastening means threaded into the body piece and throughthe cover piece for clamping said pieces together, said pieces having apassage cut to extend between them communicating their mated recesseswith the exterior of the block, an end portion of the cable extendingthrough said passage, conductor wires of said cable being secured tosaid binding posts, the walls of said passage formed with of smoothlycut ridges extending at least partially therethrough, the insulatingportions of against and conformed to the contour of said ridges to serveas a strain relief,` said passage being proportioned in cross section tosecurely clamp the cable end portion between said pieces yet per mitt-he latter'to come into abutment without injuring the cable insulation.2. In connecters for coupling electric in* sulated Wire cables of thecharacter described, a female block comprising a body piece having a cutaway portion and a cover piece,

said pieces being formed of machined fibrous a. plurality ing about aninner end of each of said memy bers when the cover piece is applied toreplace said out away portion. screw fastening means threaded into thebody piece and through the cover piece for clamping said piecestogether, a binding post carried by each of said inner ends, saidreceptacle members having sleeves terminals set back from an end surfaceof said block to shield said members against accidental short circuit,said body piece having a channel cut therein communieating said recesseswith an exterior side of the block, an 'end portion of the cableextending through the channel, conductor wires of said cable beingsecured to the binding posts, said channel formed with cut ridges 'forengaging insulating portions of the cable pressed against and conformedto the contourthereof to serve'as a strain relief, said passage beingproportioned inl cross section to securely clamp the cable end portionbetween said pieces yet permit the latterto come into abutment Withoutinjuring the cableY insulation. y

' 3. In yconnecters for coupling electric insulated wire'cables ofthecharacter described, a male block comprising a body piece having a cutaway portion anda cover piece, said pieces being formed of machinedfibrous insulating sheet material, said cover piece bev i carried byeach of said inner ends, said prong members having split pin terminalsextending from the block, said pieces having 'spaced vmating groovescuttherein communicating' said recesses with an exterior side of thejblock, conductor wires of said cable extending into said grooves, theends of sald coni ductor wire portions being secured to the bindingposts, the grooved walls of one of said piecesfrmed with smoothly cutridges for engaging insulating portions of the conductor wirespressedagainst and conformed to thecontour of the ridges to serve as astrain relief means, 'said mated channels forming passages proportionedin cross sections to securely clamp the cable conductor wires betweensaid pieces yet permitV the latter to 'come into abutment withoutinjuring the cable insulation.

4. A connecter for coupling electric insulated wire cables of thecharacter described comprising separable male and female blocks formedofmachined sheet insulating fibre', said blocks having portions thereofcut away, cover pieces formed of insulating fibre equivalent in shapeand dimensions to said cut away I portions, spaced metallic contactreceptacle members driven through uncut portions of the female block,said receptacle members having sleeve terminals set back from the endsurface of the'female block, metalic contact prong Amembers spaced tocorrespond to said receptacle members driven through an uncut portion ofthe male block, said prong members having split pin terminals extendingfrom the male block adapted to be inserted in said sleeve terminals,said male and female blocks having recesses bored in a cut surfacethereof, one recess at `theinner end of each of said contact members,said cover pieces having recesses mating with said block recesses toform housings about the innerv ends of said contact members when saidpieces are applied to replace said cut away portions, each female blockportion and its fitted cover piece havv ing a passage formedthere-between communicating their mated recesses with an exterior sideof the block, a power cable end extending'through said passa-ge, eachmale blockl portion and its fitted cover having spaced passages formedtherebetween communicating their mated recesses with the exterior sideof the block, conductor wires from an appliance extending through saidmale block passages, binding posts carried by the l inner ends of eachof the contact members, the conductor wires of said cable and appliancebeing secured to said binding posts,

said passages formed with smoothly cut l ridged wall surfaces, theinsulating portion of the cable and the appliance conductor wires beingpressed against and conformed to the contour of the ridged wall surfacesto form a strain relief for each of said blocks, said passages beingproportioned in cross section to securely clamp said cable and appliancewires between the block portions and pieces yet permit the latter tocome into abutment with the block portions, and screw fastenimg 4meansthreadedy into the block portions and extending through said pieces forclamping them in abutment.v

In testimony whereof I aiiix my signature.

JOI-IN HIGHAM.

